The FilterLOCK covers and seals the standard 1” furnace filter slots. The overlapping two-piece design allows for filter slots measuring up to 25” in width. The FilerLOCK is held securely in place by the integral magnetic fasteners. It effectively covers the filter slots situated at the side or top of metal return air ducts. It can be trimmed to fit over various sizes as necessary.
- Saves Energy - Reduces Utility Bills
- Blocks Allergens and Pollutants from Entering Ductwork
- Improves Indoor Air Quality
- Increases Furnace and A/C Lifespan
- Overlapping Design - One-size-fits-all Filters
- Magnetically Attaches to Ductwork - Quick & Easy
- Forms 90° Elbows - Sizes 4"-16"
- Installs on New or Existing Flexible Ducts
- 100% Recycled Material - Made in USA
- Quick and Easy Installation